Our South African patent application No. 78/0917 discloses a method of and a device for positioning a deflection wedge in a drill hole which has a pronounced horizontal component. The positioning device disclosed in this earlier specification makes use of a drop arm which is pivoted at one end and held at the other end by a plate which allows that end of the drop arm to drop at a predetermined angular orientation, in order to trigger a mechanism which prevents further rotation of the wedge.
The use of a drop arm has disadvantages in that it requires a considerable length in which to operate. Also, the trigger mechanism has a number of moving parts and is relatively complex. If the device is to be reset without removal from the drill hole, a return spring is required.
It is an object of the invention to provide a device for positioning deflection wedges in drill holes which has a simple trigger mechanism.